Still in production after more than 40 years, the PT6 engine designed in Longueuil (Qc) by Pratt & Whitney Canada (P&WC) truly revolutionized aviation. Canada’s first civil turbine engine, it originally weighed 270 pounds and produced 550 horsepower (while an equivalent conventional radial piston engine would have weighed at least 850 pounds!). The PT6 powered aircraft outclassed piston engines on speed, cruising altitude, low noise and vibration. Offered subsequently in numerous versions (some reaching 2000 horsepower), about 40 000 PT6 engines have been built so far, thus making the PT6 the worldwide best-selling turboprop in commercial aviation history. It’s been in use in some 100 aircraft types, including utility, corporate, regional transport, training and helicopter types. The development of a gas turbine was a turning point in P&WC history (confined before that to assembly, service and overhaul of piston engines designed by the parent company in East Hartford, USA). The piston engine future was only repair and spare parts. Gas turbine offered an option to the decline of the piston engine and allowed P&WC to start producing its own original products.
The PT6 powered aircraft outclassed piston engines on speed, cruising altitude, low noise and vibration.
The first PT6 test stand run was in November 1959 (only ten and a half months from start of layout design). The first prototype flight occurred in May 1961, and certification was achieved by December 1963. After years of effort, President Ron Riley and Engineering Manager Richard Guthrie hab been able to convince the Board to go ahead with this costly project. In 1957, Guthrie was authorized to assemble a design team. New talents were hired from Canada and the UK. With the men already in place, they provided the mixture of balanced technical experience and personal qualities which were the corner stone of continuing success. These gifted men (sometimes referred to as “The Dirty Dozen” – a humoristic reference to a popular movie) were named: Jean-Pierre Beauregard, Fernand C. Desrochers, John K. Elsworth, Fred A. Glasspoole, Richard H. Guthrie, Gordon Hardy, Herbert H. Langshur, Allan B. Newland, Gudmunder “Pete” Peterson, Jim Rankin, Elvie L. Smith and Thor E. Stephenson (who succeeded Ron Riley as President after his premature death in 1959). Other members of the project were Arthur Goss, Douglas Millar and John Vrana.